version bump for v2.4.0

Quicksilver/Configuration/Developer.xcconfig

@@ -4,7 +4,7 @@
 QS_INFO_VERSION = 2.3.0
 
 // The current development version shown in About Box
-QS_BUNDLE_VERSION = 4038
+QS_BUNDLE_VERSION = 4039
 
 // A build of Quicksilver that breaks backwards compatibility for plugins. Setting a value here will mean that all future plugins built with `bltrversion` will have a minimum QS version requirement of this value
 QS_BACKWARDS_COMPATIBILITY_BREAK = 4001